محمود ناصری

The thermaltreatmentmethodwasemployedtopreparebariumhexaferrite(Fe6 O8/Ba Fe6 O11) na- nostructure. Thismethodwasattemptedtoachievehigherhomogeneityofthe final product.Specimens of bariumhexaferritenanostructurewerecharacterizedbyvariousexperimentaltechniquesincluding X-raydiffraction(XRD),highresolutionFieldemissionscanningelectronmicroscope(FESEM)and Fourier transforminfraredspectroscopy(FT-IR). X-raydiffractionresultsshowedthattherewasnocrystallinityinthepredecessorandithadstill amorphous phase.Theformationsofcrystallinephasesofbariumhexaferritenanostructuresstarted from 673to973Kandthe final productshaddifferentcrystallitesizesrangingfrom29to48nm.The chemical analysisofthebariumhexaferritenanostructureswasperformedbyenergydispersionX-ray analysis(EDXA),demonstratedthatthebariumhexaferritenanostructurescontainedtheelementsofBa, Fe, andO.TheeffectofcalcinationtemperatureonbandgapenergywasstudiedbyUV–vis absorption spectra disclosedwhencalcinationtemperatureincreased,theappraisedbandgapenergyvaluesofthe BaFe12O19 nanostructures decreased.Theformednanostructuresexhibitedferromagneticbehaviors which wereconfirmed byusingavibratingsamplemagnetometer(VSM).ThetechniqueoftheElectron paramagnetic resonance(EPR)spectroscopywascarriedoutat300Konthecalcinedspecimensthat exhibitedthevariationoftheline-shapesofthespectraofwithcalcinationtemperature.